It is known to file sheets of paper in a cover by means of a plastically deformable strip. The strip has a central elongate anchor strip and a prong at each end. The anchor strip is substantially flat and the prongs are bent over, in the same direction, to adopt a "U"-shape. The anchor strip is secured to the cover. If any sheets of papers are to be filed, spaced holes are punched along an edge thereof, the prongs are threaded through the holes and the exposed portions of the prongs are then bent towards each other to retain the sheets of paper in the cover in a stack. If further sheets are to be added or sheets are to be removed, the prongs are straightened and further sheets added or sheets removed and the prongs are then bent towards each other to retain the desired sheets in the cover.
As an enhancement, a known further "U"-shaped filing accessory is provided having two legs with a circular cylindrical socket at each end with the tips of the prongs being receivable in these sockets. Thereby, when the prongs are straightened, the tips are inserted into the sockets and sheets of paper may then be transferred from the filing strip onto the legs of the filing accessory. With these known filing accessories there is a step between the prong and sockets which is problematical in that it makes it difficult to transfer sheets of paper from the prongs to the accessory. In this manner, if a sheet of paper in the middle of the stack is to be accessed, the sheets of paper on top of it are transferred onto the accessory, the legs of the accessory are disengaged from the prongs and the desired sheet of paper is removed. Similarly, if a sheet of paper is to be inserted into the stack instead of on top of it, the appropriate sheets of paper are transferred onto the accessory, the legs of the accessory removed from the prongs and the prongs are threaded through the holes in the further sheet of paper. The legs of the accessory are then again engaged with the prongs and the sheets of paper thereon transferred back onto the prongs. The accessory is removed and the prongs are folded over to retain the stack of papers in the cover.